Bouncing speedo

[SteveOS3]

Being extra keen to go to my first TVRCC South Wales meet tonight I should have known......

Heavy rain, never mind, a good test for the leaks I think I've fixed!!

Then a call from work just as I leave, some £"$"££" ignored the 'DO NOT EVER DO THIS' warning and screwed up the live delivery system for exhausts at a car plant!!! Drove to work, fixed it, but now way too late to go to the meet.

Then on the way home the speedo begins to oscillate 10mph either side of the actual reading, but only in 4th gear

Any ideas as to why this happens would be greatly appreciated

Off to nurse a large bottle of Stella now...........

Cheers,

SteveO

[Dave_M]

Sorry Steve, not mechanically minded, but a warm welcome to you.

I wonder if something is worn to have that effect. Doubtless someone will be along soon to help

[Gerald-TVR]

Hi Steve

Mine does exactly the same its something to do with the sender - it actually does it in all gears but in first its so low you dont notice and in top you dont see it because you dont go fast enough.

Just ignore it its a TVR quirk

[tvrgit]

Mine started to do that shortly before the ignition connector block at the switch, blew. After I fixed it the speedo was fine.

It could be that, it could be the speedo live feed or the earth.

[SteveOS3]

Thanks Dave/Gerald/TVRGit,

I hadn't noticed it before, but last night was only the second time out in the wet - maybe a damp/earthing problem so I'll take a look when I get time and let you know!

I have the plans for the garage deilvered today, with an inspection pit(hopefully) so I should be under cover in a month or two.

Cheers,

Steve

[SteveOS3]

New information!

I took her out in the rain again today and no bouncing. Then I turned the lights on..... sidelights ok but headlights caused the bouncing to start, still only happens in 4th gear but it looks like am interference problem with the lighting/instrument panel (I think )

I'll try to take a look over the weekend and post any findings.

SteveO

[mikee boy]

Ignition connector block.

[Griff 500]

Hi Steve . Good to see you on here and hope that the car is still running OK. It won't be of too much consolation but in all the three years of ownership the rev counter always did this but just in fourth! My solution was one of avoidance rather than delve into the vaguaries of TVR wiring. However the S wiring seems a breeze compared to the Griffith I've now got.